Variable speed controller mechanism



July], 1931. B. P. GRAVES I VARIABLE SPEED CONTROLLER MECHANISM FiledJan. 20, 1928 2 Sheets-Sheet l July 7, 1931. I B. P. GRAVES 1,812,871

VARIABLE SPEED CONTROLLER MECHANISM I Filed Jan. 20, 1928 2 Sheets-Sheet2- J0 1"071 a 4@ 1 W {A x L v r J :16 050 a 4 6 i Z2 32 I g 2% 2 .Q mm3% 7/1l67ee68 Patented July 7, 1931 UNITED STATES.

PATENT FFICE BENJAMIN P. GRAVES, CRAINSTON, RHODE ISLAND, ASSIGNOR TOBROWN AND SHARPE MANUFACTURING COMPANY, A CORPORATION OF RHODE ISLANDVARIABLE srEEn CONTROLLER MECHANISM Application filed January 20, 1928.Serial No. 248,187.

The-invention relates to improvements in variable speed controllermechanisms particularly adapted for use on milling ma chines andmachines of similar types ems ploying a variable speed driving mechanism"in which two ormore sets of controller devices are provided atdifferent points on the machine to enable the operatorreadily to setthemechanism for the desired speed without moving about the machine.

The invention is herein disclosed as embodied in a change speedcontroller and indicator mechanism which is-a dapted for use in amilling machine of the column and knee type and. comprises two sets ofrotary controllers and indicator dials for the table feed, one beingmounted'at the side on' the machine column and the other on the front ofthe sad dle. The two sets of controllers are interconnected so that whenone controller arm is rotated by the operator both indicator dials areproperly set to indicate the, change of speed I 1 As ordinarilyconstructed, these rotary controller arms are rotated through apredetermined angle to secure each change of speed, being heldyieldingly in position by the engagement of spring plungers mounted onthe arms with recesses formed'on relatively stationary parts of themachine- When an arm is turned by the operator. the spring plunger'oneach aim-slides out of its recess and then falls into a new recess asthearms are brought exactly to the desired position. However, due to theplay in the connections between the two sets of controls, difliculty'hasbeen experienced in bringing the second rotary controller arm exactlyinto position so that its spring plunger may register with thecorresponding'reces's and the indicator dial be sit to designate thecorrect operating spee In carrying out the present invention, a simpleand efficient mechanism is provided to enable the operator to bring bothsets of control devices into their desired position quickly andcertainly by turning either one of the rotary controller arms. Forconvenience and ease of operation'in setting the variable speedmechanism, the arm being manipulated by the operator is given a completerevolution for each change of speed so that each arm is always returnedto the same rest position. WVith the present construction the remainingarm is disconnected from the controller and indicator mechanismassociated therewith and is held locked in rest position out ofengagement with the gear shifting mechanism so that it becomesunnecessary to center this inactive arm carefully in looking positionafter each change of speed. At the same time, mechanism'is provided tobring the change speed controller and indicator mechanism associatedwith the inactive arm into register with that which is being manipulatedby the operator to indicate correctly the operating speed. l

The several features of the invention consist also in the devices,combinations and arrangement of parts hereinafter described and claimedand together with the advantages to be obtained thereby should bereadily understood by one skilled in the art from the followingdescription taken in connection with the accompanying drawings in whichFig. 1 is a view in side elevation of a portion of a milling machine ofthe column and knee type illustrating the preferred embodiment of theinvention; Fig. 2 is a detail view on an enlarged scale of the rotarycontroller and indicator mechanism for the table feed mounted on themachine column, as shown in Fig. 1; Fig. 8 is a front sectional view ofthe controller and indicator mechanism taken on the line 38 of Fig. 1; Fig. 4 is a sectional view of the rotary controller and indicatormechanism and the operating cams for the change speed gears for thetable feed; Fig. 5 is a detail sectional view taken on the line 55 of Fi g 3 illustrating particularly the connections of the rotary controllerlever with the change speed and indicator mechanisms; Fig. 6 is asectional view taken on the line 6-6 of Fig. 5; Fig. 7 is a detail viewin front elevation of the locking ring shown in section in Fig. 5; andFig. 8 is a detail sectional view of the locking ring looking from theright in F 7.

In the drawings the invention is shown embodied in a milling machine ofthe column speed mechanism which indicates and knee type such forinstance as is illustrated in the patent to Benjamin P. Graves, datedJanuary 15', 1924, No. 1,480,900. In

this machine theiixed machine base includes a column 2, in which thesp1ndle'4 1s mounted. The work is carried on a work supporting table 6mounted for longitudinal movement in a supportmg saddle 8 which 18 nturn mounted for transverse movement on p a supporting knee l0 and thisis mounted for vertical movement on the column 2 as is usual 7 in thistype of machine. The spindle and work supporting table arerelatively'moved by one or both of two variable speed mecha nismsthrough one of which variable feed-' mg movements are imparted to thetable'and the other Of'WlllCll the spindle 18' through rotatedatvariable speeds. These mechanisms are mounted in and supported by thefixed column and each'may be. adjust-ed by-a controller element mountedon the left side of the column andconveniently accessible by theoperator when standing at thi side of the column at the frearof the tablriable'speed mechanisms are adjusted is also connected with' a similarcontroller mounted upon the front of the saddle where it iswithintconvenient reach'of' the operator when at the front ofthemachine. Associated with each controller element for the variabletable feed mechanism is an indicator which brings v to view therate offeed in inches per minute corresponding to each setting of thecontroller. A similar indicatoris associated with each controller forthe variable spindle in revolutions per minute the spindle speedcorresponding to the settings of the controller;

- 22.through connections which include the.

The variable speed mechanism for driving the table is operated as hereindisclosed by means ofthe gear shifting levers 12 and 14 mounted on fixedpivots and controlled by the cams 16 and 18' respectively which are"secured on the cam shaft 20. The cam shaft is. rotated to giveithedesired variations in the table feed fromthe rotary controller arm bevelgear .24 which meshes with a bevel gear 26 secured to the. end of theshaft 28. The

shaft 28 isin t'urirconnected to rotate with a stub shaft 30 on whichthe rotary controller lever 22 is mounted through the gear 32 secured tothe shaft 28 and the gear '34 secured to the stub shaft 30. Forconvenience in setting the variable speed mechanism and ease ofoperation, the ratios of the gears 24 and 26, and 32 and 34 are arrangedto require one complete revolution of the rotary: controller arm 22 foreach succeeding adjust ment of the variablev speed mechanism.

To indicate the rateof feed resulting from the adjustment of thevariable speed mechani'sm in accordance with the number ofturns giventhe rotary 'controller arm 22 a dial 36 The 'mechanismthrough which eachofthese vameshing with a pinion 48 on the stub shaft .30 whichsupportsthe rotary controller arm 22. QThe dial is provided withgraduations which preferably indicate the rate of'feed in inches perminute correspondingtothe adjustment of the variable speed mechanism,

and-all the graduations except that corresponding to the settings ofthe, controller are preferably hidden fromview under the cas ing 40which is provided'with a slight opening'50 I at which the graduationrepresenting the present adjustment of the variablespeed mechanismappears; To'jsecure any given feed, thereforejthe operatormerely rotatespears at the sight opening. Thecasing 40 may if desired be'provided witha table indicating the various feeds. which may be secured by adjustmentof the controller arm.

The variable speed mechanismmay also ler. and indicator dial mounted onthe front of thesaddlewhich is inevery respect; the

same as that on the side ofthe column ust described. The controller arm,of thiscon: troller and indicator mechanism is connectedthrough-reduction gears to the forward end" of the shaft '52,.see Fig. 1, whichis mounted on the saddle 8 and has'a' driving sliding connectionwith ashaft 54 mounted the controller arm until the desired feed ,ap

be controlled by the operator from the front of the machine by means ofa rotary controlon the knee '10. The rear end'of the shaft I i 54is'connected by hookjoints 56' and anex 'tensibleshaft 58; with theforward end of a shaft'60 mounted inthe fixed column which 7 isconnected bevel gears 62,v 64 to the shaft 28. j When either. controllerand indicator mechanism 18 operated by the operator, they will both berotated in unison so that both: dials wlll show the present adjustmentoft-he variable speed mechanism.

Due to the fact that there is almost inevitably a certain amount of playor back lash 1n the connections above described for actuating onecontrolling mechanism from the 8 other, .difliculty' has beenencountered in brlnging the two controller mechanisms into registerwitheach other so that the operator by manipulating either of the rotarycontrollers can readily set both mechanisms to indicatethe correct feed;A feature of the present invention contemplates the provision of a"novel and at the samejtim'e simple mechment of the variable speed theoperation of the rotary anism which acts automatically to index the twocontroller and indicator mechanisms accurately with relation to eachother. Each rotary controller arm 22 is loosely mounted on'a sleevebearing 70 rigidly secured to its corresponding stub shaft 30 and isheld locked in rest position, except when being actually manipulatedby'the operator, by the engagement of a spring pressed lock bolt 7 2with a corresponding recess 7 4 in the machine frame. A knob or handle 7is secured to the end of the lock bolt 72 so that it may be readilyWithdrawn by the operator to permit controller, means hereinafterdescribed being provided v for rigidly connecting the controllerarm 22to the stu'b30 as the lock bolt is withdrawn. With this construction,each rotary controller arm, at all times, except when released by theoperator, is held in one fixed position. For each succeeding adjustgearsmade by the operator in manipulating either controller device each stubshaft should make eX- actly one revolution to bring the indicator dialsto their proper position and also to exactly position the change gearcams 16 and 18. To index the controller and indicator mechanism remotefrom the operator at the end of a revolution of the stub shafts 30, aspring'plunger 76 having a V-shaped cam surface is mounted within thecontroller arm 22, and is adapted to engage yieldingly with V acorresponding recess 78 formed in the sleeve 70. The spring pressedplunger 76 is normally permitted to retract as the stub shaft 30 isrotated, causing the V-shaped plunger 76'to ride out of its-recess 78and then acts to index the shaft 30 accurately with relation to thecontroller lever 22 at the end of one revolution so that the stub shaftis returned exactly to its original position,

Either rotary controller arm may be operatively connected to rotate itsstub shaft 30 when it is desired to effect an adjustment of the variabletable feed by mechanism which acts to hold the spring'plunger 76 rigidlyin contact with the recess 7 8. To this end, a locking member ordisk 80is secured to the lock bolt 72 and is adapted when the lock bolt iswithdrawn by the operator to engage the rear end of the spring plunger76 thus holding it rigidly in advanced position.

7 When the handle 75 is released by the operator,the lock bolt 72 actingunder the influence of its springwill move forward again carrying withit the cam and so releasing the spring plunger 76. Inasmuch as it isundesirable to permit the rotary controller lever to be disconnectedfrom the stub shaft 30in case the operator releases the knob 75 beforethe controller arm 22 has made a complete revolution to set the changefeed cams to produce the desired speed, 'means are provided which actupon turning the rotary controller arm 22 to hold the spring plunger 76in the recess 78 to lock the rotary con troller lever 22 to the stubshaft 30. This mechanism comprises a fixed ring 82 surrounding thecollar 70 and adapted to ride in a corresponding groove 84 formed in thespring plunger 76. The ring is provided with a recess 86 so that in therest position of the rotary controller arm 22 the spring plunger is freeto move out of contact with t 1e recess 78 to permit the stub shaft 30With the collar 70 to move independently of the rotary controller arm22.

The nature and scope of the invention havin g been indicated and oneembodiment there of having been described, what is claimed 1s 1. In amachine tool the combination with a variable speed mechanism of aplurality P of variable speed controller mechanisms located at differentpoints on the machine each comprising a shaft rotatable to effectsucceeding adjustments of the variable speed mechanism, means forcorrecting the position of the shaft to bring it into an exact angularposition for each adjustment of the variable speed mechanism, a manuallyoperable rotary controller mounted to turn on the shaft, an indicatordial, connections for causing each dial to indicate the presentadjustment of the variable speed mechanism, and means controlled by theoperator to positively connect the rotary controller to rotate theshaft.

2. In a machine tool the combination with 1".

a variable speed mechanism of a plurality of variable speed controllermechanisms located at different points on the machine each comprising ashaft rotatable to effect succeeding adjustments of the variable speedmechanism, a manually operable rotary controller mounts ed to turnthereon, means for indicating the present adjustment of the variablespeed mechanism, means controlled by the operator to positively connectthe rotary controller to rotate the shaft, and means out of the controlof the operator to maintain the connection until the rotation of theshaft to effect an adjustment has been completed.

3. In a machine tool the combination with i a variable speed mechanismof a plurality of variable speed controller mechanisms located atdifferent points on the machine each comprising a shaft rotatable toeffect succeeding adjustments of the variable speed mech- 11:

anism, a manually operable rotary controller mounted to turn thereon,means for indicating thepresent adjustment of the variable speedmechanism, means for locking the rotary controller against movement withthe iii shaft, and means rendered operative upon releasing the rotarycontroller to operatively connect the shaft to turn therewith.

4. In a machine tool the combination with a variable speed mechanism ofa plurality of variable speed controller mechanisms located at differentpoints on the machine each comprisinga shaftrrotatable to effectsucceedrelation to the rotarycontroller.

I V nation with a v'ariable'speed mechanism of a plurality ofingadjust-ments of the variable'speed mechanism, a manually operablerotary controller mounted. to turn thereon, means for connecting thecontroller to the shaft, means for indicating the present adjustment'ofthe variable speed mechanism,vmeans for locking the rotary controllerwhennot beingmoved by the operator againstmovement with the shaft, andmeans acting at each speed adjustment of the variable speed mechanism tocause the shaft to assume an'eXact angular 'In a machine tool the combvariable speed controller mechanism located at different points on'themachine each comprising a shaft rotatable through a predetermined anglefor each succeeding adjustment of the variable speed mechanism, amanually operable rotary controlleramounted to turn thereon, anindicator dial, connections for causing eachdial to indicate the presentad-v j justment o-fthe variable speed mechanism,

means for locking the rotary controller in a predetermined angularposition, a yielding cam connection for indexing V relation to'therotary controller to cause the controller mechanism to correspondexactly to the present speed adjustment-of the variable speed mechanism,and means actuated upon releasing the rotary controller to render thecam connection rigid to connect the shaft to turnwith the rotarycontroller.

6. In a machine tool the combination with a variable speed mechanism ofa plurality of variable speed controller mechanisms located at differentpointson the machine each comprising amanually operable rotarycontrolleradapted to effect succeeding adjustments of the variable speedmechanism,- means for in dicating the present adjustment of the variablespeed mechanism, means controlled by the operator for rendering therotary controller 7 active to change the'adjustment of the variamanuallyoperable rotary controller, mech anism including a gear train throughwhich each revolution of the controller efiects. one

succeeding adjustment in a cycle ofadjust ments of the variable speedmechanism, means for holding therotary controller in the same restposition to which it is returned-after each adjustment of the variablespeedmechanism,

an indicator dial, connections for indexing the variable speedmechamsmwith relation to the rotary controller in its rest position,

- ustment, and

the shaft with andmechanism controlled from the: rotary controller forcausing the dial'to-indicate the adjustment of the variable speedmechanism. 7 8. In a machine'tool the combination with a variable speedmechanism of a plurality of vvariable speed controller mechanismslocated at different points on the machine each comprising a manuallyoperable rotary controller andan indicator dial, connections for causingeach dial 'to indicate the adjustment "of the variable speed mechanism,means for indexing each controller mechanism lIldG- pendently for eachspeed adjustment tocorrespond exactly with the variable speed ad meanscontrolled by the operator for rendering-the rotary controller operativeto adjust the' variable speed mechanism.

9. In a machine tool the'combination with'a variable speed mechanism ofa plurality of variable speed controller mechanisms located at differentpoints on the machine each comprising a manually operable rotarycontroller adapted for each revolution of the controller to effect onesucceeding adjustment in the cycle of adjustments of the variable speedmechanism, means for indicating the present adjustment of the variablespeed mechanism, means for locking the rotary controller againstrotation duringtheadjustment of the variable speed controller mechanismby another controller, and means controlled by the operator forrendering the rotary controller active to adjust the variable speedmechanism. v v 10. In a machine tool the'combination with a variablespeed mechanism of a plurality of variable speed controller mechanismslocated at different points on the machine each comprising a manually o''erable rotary controller adapted to effect "succeeding adjustments ofthe variable speedvmechanism, meansfor indicating the present adjustmentof the-variable speed mechanism, means for locking the rotarycontroller. against irotation during the adjustment of the variablespeed controller mechanism by anothercontroller, and means controlled bythe operator for rendering th'e rotary'controller active to adjust thevariable speed mechanism. v 11. In a machine tool the combination with avariable speed mechanism of'a plurality of variable speedcontroller'mechanisms located at different points on the machine eachcomprising a manually operable rotary controller adapted to 7 effectsucceeding adj ustments of the variable speed mechanism, means for in?dicating the present adjustment of the'variable speed mechanism, meansfor locking the rotary controller against movement during the adjustmenttroller mechanism I by another controller,

ing the rotary controller operative to adjust of thenvariablei speedconmeans controlled by the operator for render- 7 for indexing eachcontroller mechanism to variable speed controller mechanisms located atdifferent points on the machine each comprising a manually operablerotary controller adapted to effect succeeding adjustments of thevariable speed gearing, means for indicating the present adjustment ofthe variable speed mechanism, a shaft forming part of the controllermechanism on which the rotary controller is mounted to turn, a springpressed cam carried by the rotary controller for indexing the shaft withrelation to the rotary controller, a lock bolt carried on therotarycontroller to lock the rotary controller against movement with theshaft, and means rendered active by withdrawing the lock bolt to lockthe cam to operatively connect the.

rotary controller with the shaft.

13. In a machine tool the combination with a variable speed mechanism ofa plurality of variable speed controller mechanisms located at differentpoints on the machine each comprising a manually operable rotarycontroller adapted to effect succeeding adjustments of the variablespeed mechanism and means for indicating the present adjustment of thevariable speed mechanism, a shaft forming part of the controllingmechanism on which the rotary controller is mounted to turn a springpressed cam carried by the rotary controller, a lock bolt carried on therotary controller to lock the rotary controller against movement withthe shaft, a locking 'member actuated by the movement of the lock boltholding the spring pressed cam to operatively connect the rotarycontroller with the shaft, and a locking ring adapted to lock thespringpressed cam in position during the movement of the rotary controller.

14. In a machine tool the combination with a variable speed mechanism ofa plurality of variable speed controller mechanisms located at differentpoints on'the machine each comprising a shaft rotatable to effectsucceeding adjustments of the variable speed mechanism, a manuallyoperable rotary controller mounted to turn thereon, means for indicatingthe present adjustment of the variable speed mechanism, a V-shapedspring pressed plunger carried by the rotary controller and adapted toengage a corresponding recess on the shaft, a lock bolt carried on therotary controller to lock the rotary controller against movement withthe shaft, means rendered active by the operator in withdrawing the lockbolt to hold the plunger in contact with the recess, and a locking ringadapted to lock the plunger in its recess during the rotation of therotary controller.

15. In a machine tool the combination with a variable speed mechanism ofa plurality of variable speed controller mechanisms located at differentpoints on the machine, each comprising a shaft rotatable through onerevolution for each succeeding adjustment in a cycle of adjustments ofthe variable speed mechanism, means for indicating the presentadjustment of the variable speed mechanism, a manually operable rotarycontroller loosely mounted on each shaft, means for connecting therotary controller to rotate the shaft, and means for hOlCllIlg therotary controller when out of operation in the same predeterminedangular position on the machine.

16. In a machine tool the combination with a variable speed mechanism ofa plurality of variable speed controller mechanisms located at differentpoints on the machine, each com n-ising a shaft rotatable through onerevolution for each succeeding adjustment in a cycle of adjustments ofthe variable speed mechanism, means for indicating the presentadjustment of the variable speed mechanism,

a manually operable rotary controller loosely mounted on each shaft,means for connecting the rotary controller at a predetermined angularposition on the shaft, and means for determining the stop position ofthe controller to secure an accurate adjustment of the variable speedmechanism.

In testimony whereof I have signed my name to this specification.

BENJAMIN P. GRAVES.

